A common experience of callers to service bureaus and businesses is that they are put on hold while the called party goes off to find information, make confirmations, check stock, take another call, etc. "Hold" is a call state invoked by a party to the call via signalling from his or her telephone set that results in the call being disconnected from that party's telephone set but remaining connected to the switching system that serves that party's telephone set, ready to be reconnected to that party's telephone set on demand.
Being placed on hold for more than a few seconds is normally an unpleasant and frustrating experience for most people. It is waiting time, unproductive time that could be better-spent doing other things. As a consequence, significant numbers of people who are put on hold for more than a brief time usually abandon their calls and hang up in resentment and frustration. The result is bad customer relations, wasted effort, and lost business for the service bureaus or businesses that put the people on hold. Furthermore, the hold state results is a waste of telephone network resources. It unproductively ties up the held party's telephone set as well as the telephone lines, trunks, and switching resources being used to maintain the connection of the held call from the held party to the switching system serving the other party. If freed, these resources could be used productively for other calls.
To combat a related problem--call abandonment due to delays in service-bureau agents answering and handling calls in the first place--many call centers have in recent years implemented automatic call-back systems. These work generally as follows. When an incoming call is not answered by an agent within a predetermined period of time (e.g., three rings), a call-back system automatically answers the call and plays a pre-recorded announcement to the caller giving him or her the option of either having the call placed in a queue to wait for an agent to pick it up, or hanging up and being called back when an agent becomes available. If the caller selects the call-back option, the system either obtains the caller's telephone number automatically from the telephone network by means of Automatic Number Identification (ANI), or requests the number from the caller. The caller then hangs up. When an agent becomes available, the system uses the caller's number to automatically place a new call to the caller and connects the call to the available agent. Illustrative systems of this nature are disclosed in U.S. Pat. Nos. 5,185,782 and 5,155,761. Unfortunately, such automatic call-back systems do nothing to alleviate the first-mentioned problem resulting from a caller being placed on hold by the agent, after the call has been connected to the agent and handling of the call by the agent has commenced.
In an attempt to alleviate these problems, a number of arrangements have been proposed that alert the party that has been placed on hold to when he or she is taken off hold. The alerting normally takes the form of an audio signal generated at the held party's telephone set. Its function is to allow the party who has been placed on hold to relax or do something else instead of having to cradle the telephone handset to his or her ear listening for the other party to return and take the call off hold. By thus making the time spent on hold less annoying for the held parties, these arrangements are effective in reducing the instances of the held parties abandoning the calls. Illustrative examples of such arrangements are disclosed in U.S. Pat. No. 4,731,822 and Japanese Pat. No. 60-136498. Unfortunately, these arrangements are often complex and expensive to implement, and difficult or impossible to retrofit into existing telephone networks. Moreover, they do nothing to cure the aforementioned problem of waste of telephone network resources that results from a call languishing in the on-hold state.